Italy, Venice - San Salvador church

San Salvador is a church in Venice, Italy, known for its historical and architectural significance. Originally consecrated in 1170, it underwent major reconstruction starting in 1508. The church features a unique design with three Greek crosses and domes. The facade was added in 1663, and the adjoining monastery now serves as office space. San Salvador remains an active parish church and cultural center, with a notable cannonball embedded in its facade from an 1849 bombardment.

Which Pope was involved in the church's early history?

What significant event is associated with the cannonball embedded in the column?